inflammatory cells increased in painful human tendinopathy?  A systematic review

BJF, Gettings P, Dakin SG, & Carr AJ. Br J Sports Med. Published
Online First: September 2015; doi: 10.1136/bjsports-2015-094754.

Take Home Message: Tendon-related issues seem to have
increased inflammation, while torn tendons have significantly lower
inflammation than tendon-related conditions in intact tendons.

injuries (e.g., tendinosis, tendonitis, tendinopathy) cause pain and limit
function.  However, questions remain as
to whether or not they are inflammatory in nature.  This is an important question since it could
influence our treatment strategies. Therefore, the authors of this systematic
review aimed to determine if inflammatory cells were increased in tendinopathy
as well as to see the relationship between inflammatory cells and
symptoms.  The authors conducted a literature
search of Medline and found 5 studies that compared inflammatory
cell counts in tendon tissue from participants with tendinopathy and to healthy
controls.  Among the 5 articles, 3
included the rotator cuff, 1 included the Achilles tendon, and the last one
evaluated the patellar tendon.  The
studies ranged from 6 to 10 (on a 10 point scale) for study quality as assessed
by the authors.  The included studies
demonstrated that there tendons with tendinopathy had more inflammatory cells (for
example, macrophages and mast cells) compared with healthy tissue, yet only
3 of the studies included statistical analyses of the quantitative results.  The authors also reported that intact tendons
with tendinopathy had less inflammatory cells in 2 studies compared with torn
tendons.  Based on 1 study, there was no
relationship between inflammatory cells and symptoms.

review could be very informative when selecting treatments for patients with
tendinopathy because the authors concluded that there is an inflammatory
components to tendinopathy. They also noted that the evidence supports the
presence of chronic inflammation but not acute inflammation.  Therapies, such as anti-inflammatory
treatments, may help individuals suffering with tendinopathy.  Future studies should investigate the effects
of anti-inflammatory therapies within this population.  However, the generalizability of this review
is concerning since there is some debate amongst sports medicine professionals
as to the cause of tendon-related conditions, such as tendinosis being
degenerative or tendonitis being inflammatory. 
This review included each of these conditions as well as the overarching
tendinopathy.  The possible heterogeneity
of tendinopathies may indicate that inflammatory cell counts could be different
based on the nature of the condition, ultimately influencing the effectiveness
of the treatment.  An earlier post on SMR highlighted a study
that showed early tendinitis may be inflammatory, but that this is not often
seen in chronic tendinitis.  It is
interesting to see that torn tendons have lower inflammatory counts than tendinopathic
tendons, but the question remains as to whether the inflammation lowering
occurred before or after the tear itself. 
Ultimately, this highlights the need for more research in this area, but
as clinicians anti-inflammatory therapies may be an option when treating
patients with tendinopathies. 

for Discussion:  Are there any treatments
that you use for tendon-related pathologies? 
Are there any clinical findings that you use to differentiate between
specific tendinopathies (tendinosis vs. tendinitis)?

by: Nicole Cattano
by: Jeffrey Driban


Dean BJ, Gettings P, Dakin SG, & Carr AJ (2015). Are inflammatory cells increased in painful human tendinopathy? A systematic review. British Journal of Sports Medicine PMID: 26246419